1.\" Copyright (c) 1992, 1993 2.\" The Regents of the University of California. All rights reserved. 3.\" 4.\" This code is derived from software developed by the Computer Systems 5.\" Engineering group at Lawrence Berkeley Laboratory under DARPA contract 6.\" BG 91-66 and contributed to Berkeley. 7.\" 8.\" Redistribution and use in source and binary forms, with or without 9.\" modification, are permitted provided that the following conditions 10.\" are met: 11.\" 1. Redistributions of source code must retain the above copyright 12.\" notice, this list of conditions and the following disclaimer. 13.\" 2. Redistributions in binary form must reproduce the above copyright 14.\" notice, this list of conditions and the following disclaimer in the 15.\" documentation and/or other materials provided with the distribution. 16.\" 3. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)kvm_getprocs.3 8.1 (Berkeley) 6/4/93 33.\" 34.Dd November 22, 2011 35.Dt KVM_GETPROCS 3 36.Os 37.Sh NAME 38.Nm kvm_getprocs , 39.Nm kvm_getargv , 40.Nm kvm_getenvv 41.Nd access user process state 42.Sh LIBRARY 43.Lb libkvm 44.Sh SYNOPSIS 45.In kvm.h 46.In sys/param.h 47.In sys/sysctl.h 48.In sys/user.h 49.Ft struct kinfo_proc * 50.Fn kvm_getprocs "kvm_t *kd" "int op" "int arg" "int *cnt" 51.Ft char ** 52.Fn kvm_getargv "kvm_t *kd" "const struct kinfo_proc *p" "int nchr" 53.Ft char ** 54.Fn kvm_getenvv "kvm_t *kd" "const struct kinfo_proc *p" "int nchr" 55.Sh DESCRIPTION 56The 57.Fn kvm_getprocs 58function returns a (sub-)set of active processes in the kernel indicated by 59.Fa kd . 60The 61.Fa op 62and 63.Fa arg 64arguments constitute a predicate which limits the set of processes 65returned. 66The value of 67.Fa op 68describes the filtering predicate as follows: 69.Pp 70.Bl -tag -width 20n -offset indent -compact 71.It Dv KERN_PROC_ALL 72all processes and kernel visible threads 73.It Dv KERN_PROC_PROC 74all processes, without threads 75.It Dv KERN_PROC_PID 76processes with process ID 77.Fa arg 78.It Dv KERN_PROC_PGRP 79processes with process group 80.Fa arg 81.It Dv KERN_PROC_SESSION 82processes with session 83.Fa arg 84.It Dv KERN_PROC_TTY 85processes with TTY 86.Fa arg 87.It Dv KERN_PROC_UID 88processes with effective user ID 89.Fa arg 90.It Dv KERN_PROC_RUID 91processes with real user ID 92.Fa arg 93.It Dv KERN_PROC_INC_THREAD 94modifier to return all kernel visible threads when filtering 95by process ID, process group, TTY, user ID, and real user ID 96.El 97.Pp 98The number of processes found is returned in the reference parameter 99.Fa cnt . 100The processes are returned as a contiguous array of kinfo_proc structures. 101This memory is locally allocated, and subsequent calls to 102.Fn kvm_getprocs 103and 104.Fn kvm_close 105will overwrite this storage. 106.Pp 107The 108.Fn kvm_getargv 109function returns a null-terminated argument vector that corresponds to the 110command line arguments passed to process indicated by 111.Fa p . 112Most likely, these arguments correspond to the values passed to 113.Xr exec 3 114on process creation. 115This information is, however, 116deliberately under control of the process itself. 117Note that the original command name can be found, unaltered, 118in the p_comm field of the process structure returned by 119.Fn kvm_getprocs . 120.Pp 121The 122.Fa nchr 123argument indicates the maximum number of characters, including null bytes, 124to use in building the strings. 125If this amount is exceeded, the string 126causing the overflow is truncated and the partial result is returned. 127This is handy for programs like 128.Xr ps 1 129and 130.Xr w 1 131that print only a one line summary of a command and should not copy 132out large amounts of text only to ignore it. 133If 134.Fa nchr 135is zero, no limit is imposed and all argument strings are returned in 136their entirety. 137.Pp 138The memory allocated to the argv pointers and string storage 139is owned by the kvm library. 140Subsequent 141.Fn kvm_getprocs 142and 143.Xr kvm_close 3 144calls will clobber this storage. 145.Pp 146The 147.Fn kvm_getenvv 148function is similar to 149.Fn kvm_getargv 150but returns the vector of environment strings. 151This data is 152also alterable by the process. 153.Sh RETURN VALUES 154The 155.Fn kvm_getprocs , 156.Fn kvm_getargv , 157and 158.Fn kvm_getenvv 159functions return 160.Dv NULL 161on failure. 162.Sh SEE ALSO 163.Xr kvm 3 , 164.Xr kvm_close 3 , 165.Xr kvm_geterr 3 , 166.Xr kvm_nlist 3 , 167.Xr kvm_open 3 , 168.Xr kvm_openfiles 3 , 169.Xr kvm_read 3 , 170.Xr kvm_write 3 171.Sh BUGS 172These routines do not belong in the kvm interface. 173